Method and apparatus for decontamination of tubing

ABSTRACT

Embodiments of the invention generally provide an apparatus and method for decontaminating tubing. The invention is particularly suitable for decontaminating tubing in a test system used for certifying a filter in a containment system. In one embodiment, a test system for a containment system is provide that includes a sample system including equipment adapted for testing a filter disposed in a containment system utilizing samples obtained from a downstream sample port and a upstream sample port of the containment system, and a device for reversing a flow within the sample system. In another aspect of the invention, a method for decontaminating tubing is provided. In another embodiment, the method includes flowing a sterilization agent through tubing in a first direction and flowing the sterilization agent through tubing in a second direction.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is related to U.S. patent application Ser. No.12/163,384, filed on Jun. 27, 2008, which is incorporated by referencein its entirety.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The embodiments described herein generally relate to an apparatus andmethod for decontaminating tubing using an aerosol, vapor or gaseousdecontamination or sterilization agent, and more particularly,embodiments described herein relate to a system and method fordecontaminating a containment system and containment filter testingsystem.

2. Description of the Related Art

Numerous facilities handle hazardous and potentially fatal compoundsand/or particles. These facilities include, for example, biologicalsafety labs, pharmaceutical manufacturing facilities, biotechnologyresearch labs, and production facilities. The hazardous particulates mayinclude anything that is harmful or fatal to humans including, but notlimited to, viruses, bacteria, chemicals, and waste products. Typicallya containment system in the facility prevents the hazardous particlesfrom escaping from the facility by filtering the air exiting hazardousareas prior to entering the surrounding environment.

The containment system typically consists of multiple componentsarranged in series. The components generally include one or more filterhousing sections, one or more filters disposed in the one or more filterhousing sections, an upstream test section, a downstream test section,and an air tight damper for isolating the containment system from theupstream and downstream ductwork that the containment system is coupledthereto.

The performance of the filters disposed in the containment system iscritical to prevent human exposure to the hazardous particles.Therefore, it is necessary to certify the performance (e.g., leak and/orfiltration efficiency) of the filters on a regular basis. Thecertification process ensures that the filters are meeting predefinedoperations criteria and/or standards. In-situ filter certification isoften required for filters handling hazardous particles after thefilters installation into the contamination housing. In-situ filtertesting is performed by injecting an aerosol challenge upstream of thefilter at a known concentration, flowing the aerosol laden air throughthe filter typically at an operational flow rate, and sampling the airdownstream of the filter to determine at least one of a leak (such aspin-hole or edge) or an overall filtration efficiency of the filterbased on a predefined filtering performance criteria.

There are two current methods for in-situ certification of a containmentsystem. The first method uses two by-pass ports on the containmenthousing. A first port is upstream of the filter and a second port islocated downstream from the filter. These ports are normally closed. Tocertify the filters, the containment system is turned off causing thefacility to be shut down. The upstream and downstream dampers are closedwhile the inside of the containment housing is decontaminated byexposure to a decontamination agent. The ports are then opened to allowaccess to the filter during testing of the filter. The downstream damperand exhaust may be opened to allow the air and aerosol to pass throughthe filter. Since the containment system has been decontaminated andisolated from the upstream duct work, it is safe to test the filter inthe containment system while allowing the air to flow through theexhaust and into the environment.

The second method for in-situ certification of the containment systemuses air from the facility. This method requires both the laboratory andthe containment housing be decontaminated prior to filter testing.During decontamination, the upstream and downstream dampers of thehousing must be closed. When decontamination is complete the dampersopen thereby allowing air from the lab or other work area into thecontainment system. An aerosol challenge is introduced into the airflowing through the filter to facilitate testing of the filter.

The methods described above are costly and time consuming. The testingprocess requires the facility and/or the containment system to be shutdown during filter testing. The shutdown and decontamination may takeseveral hours and even days in some cases. Ongoing research may need tobe stopped temporarily or abandoned altogether. Moreover, it isdifficult to effectively decontaminate the entire network of tubingutilized to test the filter disposed within the containment system.Thus, higher concentrations of decontaminant agents or longer soak timesmust be utilized in order to ensure a safe environment. The loss of timeof the facility during a decontamination cycle may cost the facilitymillions of dollars due to lost research time or production time.

Therefore, there is a need for an improved method and apparatus forconducting decontamination and testing a filter in a containment system.

SUMMARY OF THE INVENTION

Embodiments of the invention generally provide an apparatus and methodfor decontaminating tubing and small spaces. The invention isparticularly suitable for decontaminating tubing in a test system usedfor certifying a filter in a containment system. It is well understoodand documented that proper environmental conditions must exist in orderto obtain effective decontamination of a space and the surface thatexist within or enclose that space. The proper temperature, relativehumidity, agent concentration and exposure to thesterilization/decontamination agent must be provided. Because of theexistence of relatively long tubes, restrictions, valves, orifices,pumps, filters and other complex surfaces and spaces in the system andbecause of the development of both high and low pressure regions,turbulence and dead zones when there is flow in the system, it is notreliably possible to provide adequate environmental conditions to assuredecontamination in every part of the system in a normal running mode.Embodiments of the invention include apparatus and methods thatcompensate for and overcome these limitations resulting in overallconditions adequate for acceptable decontamination.

In one embodiment, a test system for a containment system is providethat includes a sample system including equipment adapted for testing afilter disposed in a containment system utilizing samples obtained froma downstream sample port and a upstream sample port of the containmentsystem, and a device for reversing a flow within the sample system.

In other embodiments, the test system may include at least one of areversible vacuum pump; at least one valve having a first state thatallows flow from the sample system into a vacuum pump, the flow causinga first directional flow within the sample system, and a second statethat prevents flow from the sample system into the vacuum pump, the atleast one valve also allowing a second directional flow through thesample system that is opposite of the first directional flow; and atleast one valve having a first state that couples the inlet of a vacuumpump to the sample system and a second state that couples an outlet ofthe vacuum pump to the sample system.

In another aspect of the invention, a method for decontaminating tubingis provided. In another embodiment, the method includes flowing asterilization or decontamination agent through tubing in a firstdirection and flowing the agent through tubing in a second direction.

In another embodiment, a method for decontaminating tubing in a testsystem coupled to a containment system is provided that includesoperating a vacuum pump to create a flow of sterilization ordecontamination agent in a test system in a first flow direction, thetest system coupled to the containment and configured to test a filtertherein, and reversing the flow direction of the agent in the testsystem.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute apart of the specification, schematically illustrate the presentinvention, and together with the general description given above and thedetailed description given below, serve to explain the principles of theinvention.

FIG. 1 depicts a simplified schematic diagram of an exemplarycontainment system coupled to a test system having a flow reverseraccording to one embodiment of the invention.

FIGS. 2A-B are schematic diagrams of one embodiment of a flow reverserin different operational states.

FIGS. 2C-D are schematic diagrams of another embodiment of a flowreverser in different operational states.

FIG. 3 is a flow diagram of one embodiment of a method fordecontaminating tubing.

FIG. 4 is a chart depicting a sequence of flow direction through tubingduring one embodiment of a method for decontaminating tubing.

FIG. 5 depicts a section view of the containment system according to oneembodiment of the invention.

FIG. 6 depict one embodiment of a decontamination system.

FIG. 7 depicts a simplified schematic diagram of another embodiment of acontainment system according to one embodiment of the invention.

FIG. 8A depicts a view of one valve assembly according to oneembodiment.

FIG. 8B depicts a schematic view of a containment system coupled to asample system and a decontamination system according to one embodiment.

FIG. 8C depicts a schematic view of a plurality of valve assembliescoupled to a containment system, a sample system and a decontaminationsystem according to one embodiment.

To facilitate understanding, identical reference numerals have beenused, where possible, to designate identical elements that are common tothe figures. It is contemplated that elements of one embodiment may bebeneficially incorporated in other embodiments without furtherrecitation.

DETAILED DESCRIPTION

FIG. 1 depicts a simplified schematic diagram of an exemplarycontainment system 100 having a reversible flow test system 104according to one embodiment of the invention. The reversible flow testsystem 104 is utilized to test a filter 112 disposed in the containmentsystem 100. The reversible flow test system 104 is adapted to interfacewith a decontamination system 130. The decontamination system 130 isconfigured to provide a sterilization agent suitable for sterilizing thereversible flow test system 104. The terms sterilization agent anddecontamination agent are used interchangeably herein to describe anyvaporous, aerosol or gaseous element or compound used to clean, destroyor render harmless hazardous or viable materials or microorganisms ortheir spores that may be present in the test system 104 after testingthe filter. In one embodiment, the sterilization or decontaminationagent is an agent approved or recognized by the United States Center forDisease Control (CDC), the Food and Drug Administration (FDA), TheNational Science Foundation (NSF) or the Environmental Protection Agency(EPA).

The containment system 100 ensures that air exiting or being recycled ina facility is substantially free of hazardous particles. The containmentsystem 100 includes a housing 102 having one or more filters 112disposed therein. The containment housing 102 coupled to the reversibleflow test system 104 by one or more tubes 106. One containment housing102 that may be adapted to benefit from the invention is described inU.S. patent application Ser. No. 11/380,737, filed Apr. 28, 2006, whichis incorporated by reference. Another containment housing 102 that maybe adapted to benefit from the invention is a CAMCONTAIN™ ContainmentSystem, available from Camfil Farr, Inc., located in Washington, N.C. Itis contemplated that other containment housings and other filter testequipment, including those available from other manufacturers, may beadapted to benefit from the invention. A more detailed description of acontainment housing similar to the housing 102 is provided withreference to FIG. 7 below.

The containment housing 102 generally includes an inlet port 108 and anoutlet port 110. The inlet port 108 receives air or other gases from aworking environment of a facility, such as a biological safety lab,pharmaceutical manufacturing facility, biotechnology research lab, flowbench, or production facility, among others. The filter 112 disposed inthe containment housing 102 is arranged such that air or other gasesentering the containment housing 102 through the inlet port 108 mustpass through and be filtered by the filter 112 prior to exiting thecontainment housing 102 through the outlet port 110. Dampers 132 may beutilized to control the rate of flow through the ports 108, 110 and/orto isolate an interior volume 134 of the containment housing 102 fromupstream and/or downstream duct works. The containment housing 102 alsoincludes a bag-in/bag-out filter replacement port 114 sealable by a door128 for removing and replacing the filter 112 in the conventionalmanner.

The reversible flow test system 104 includes the test equipmentnecessary to test the filter 112 disposed within the housing 102, suchas an aerosol generator 116, a diluter 118, a sampling system 120, avacuum pump 122 and a flow reverser 124 coupled by tubing. The aerosolgenerator 116 supplies an aerosol challenge to the upstream side of thefilter 112. The aerosol generator 116 provides the aerosol in asufficient concentration to provide a statistically valid test of thefilter 112.

The sampling system 120 includes a photometer, particle counter, orother equipment suitable for leak and/or efficiency testing of thefilter 112. The sampling system 120 provides a metric indicative of thenumber of particles present in the air samples. The sampling system 120obtains air samples from one or more probes 126 or ports positioneddownstream of the filter 112 mounted in the housing 102. The probes 126may be stationary or configured to scan the downstream face of thefilter 112, as known in the art. The sampling system 120 also obtainssamples from one or more ports positioned upstream of the filter 112mounted in the housing 102. The diluter 118 is utilized to reduce theparticle concentration of the sample obtained upstream of the filter 112prior to entering the sampling system 120 as known in the art. Thedifference in the number of particulates in the samples taken from theupstream samples relative to the downstream samples may be utilized todetermine filter efficiency and/or pin-hole leaks in the filter 112.

The vacuum pump 122 aides in circulation of the air sample and/or asterilization agent from the decontamination system 130 through thesampling system 120. Any suitable pump may be used so long as the pumpis compatible with the sterilization agent.

The vacuum pump 122 is coupled to the sampling system 120 and thedecontamination system by the flow reverser 124. In one embodiment, theflow reverser 124 includes one or more valves, such as a spool valve orflow circuit comprised of appropriate shut-off valves and tees, arrangedto switch selectively reverse the direction of the flow of thesterilization agent through the sampling system 120 by changing thestate of the one or more valves comprising the flow reverser 124.

FIGS. 2A-B are schematic diagrams of one embodiment of the flow reverser124 in different operational states. In the embodiment depicted in FIG.2A, the flow reverser 124 is a spool valve that includes a first port202 connected to the test system 104, a second port 204 connected to aninlet of the decontamination system 130, a third port 206 connected toan outlet of the decontamination system 130, a fourth port 208 connectedto an inlet of the vacuum pump 122, a fifth port 210 connected to anoutlet of the vacuum pump 122 and a sixth port 212 coupled to thehousing 102. Alternatively, the sixth port 212 coupled to atmospherethrough a HEPA filter 216 (shown in phantom) instead of being coupled tothe housing 102.

Operational state of the flow reverser 124 is controlled by an actuator214. In different operational states, different ports of the flowreverser 124 are respectively connected. The actuator 214 of the flowreverser 124 may be electric, pneumatic, hydraulic, manual or other typeof actuator.

A first operational state of the flow reverser 124 is depicted in FIG.2A. In the first operational state of the flow reverser 124, the firstport 202 is coupled to the fourth port 208, the second port 204 iscoupled to the fifth port 210 and the third port 206 is coupled to thesixth port 214. In the first operational state, the vacuum pulled by thevacuum pump 122 creates pressure gradient across the test system 104.The pressure gradient in the test system 104 includes a low pressureregion 222 proximate the flow reverser 124 and a high pressure region220 proximate the test system 104. As the relative humidity isproportional to pressure, the relative humidity within the test system104 is highest in the high pressure region 220 proximate the housing 102and lowest in the low pressure region 222 proximate the pump 122 andflow reverser 124.

A second operational state of the flow reverser 124 is depicted in FIG.2B. In the second operational state of the flow reverser 124, the firstport 202 is coupled to the fifth port 210, the second port 204 iscoupled to the sixth port 214 and the third port 206 is coupled to thefourth port 208. In the second operational state, the vacuum pulled bythe vacuum pump 122 pulls the sterilization agent produced by thedecontamination system 130 through the vacuum pump 122 and pushes thesterilization agent into the test system 104, thereby creating adifferent pressure gradient across the test system 104. The pressuregradient in the test system 104 is now opposite of the pressure gradientpresent in the system 104 when the flow reverser 124 is in the firstoperational state, such that the pressure gradient in the test system104 now has the low pressure region 222 proximate the housing 102 andthe high pressure region 220 proximate the pump 122 and flow reverser124. As the relative humidity is proportional to pressure, the relativehumidity within the test system 104 is now highest proximate the vacuumpump 122.

It has been found that the effectiveness of the sterilization agent isgreater in regions of the test system 104 having moderately highrelative humidity. The presence of a moderately high relative humidityincreases the concentration of the sterilization agent on the surfacesof the tubing of the test system 104 and other surfaces. The humidity ofthe sterilization agent in the test system 104 may be controlled tobetween about 60 to 80 percent relative humidity (RH), such as 65 to 75percent RH, for good decontamination results. Thus, by changing thestate of the flow reverser 124, the humidity gradient within the testsystem 104 is reversed to ensure that portions of the test system thatlow pressure/humidity only during a portion of the decontaminationcycle, and are exposed to higher pressure/humidity during other portionsof the decontamination cycle. Thus, by decontaminating the test system104 with the flow reverser 124 changed at least once between the firstand second operations states, good humidity levels throughout the entiretest system 104 are achieved to ensure effective sterilization withminimal soak times.

The flow reverser 124 or flow circuitry coupled thereto may also includea shut-off valve 240, a by-pass valve 242 and a HEPA filter 246. Theshut-off valve 240 is disposed between the fourth outlet port 208 of theflow reverser 124 and the inlet of the vacuum pump 122. The shut-offvalve 240 has a normally open state, but may be selectively closed toisolate the inlet of the vacuum pump 122 from the test system 104 duringoptional soak periods of the decontamination cycle (i.e., periods of noflow within the test system 120). With the shut-off valve 240 closed,the pressure gradient within the test system 104 begins to dissipate,and the pressure and humidity within the low pressure region 222 beingsto rise while the pressure and humidity in the high pressure region 220falls, thereby increasing the effectiveness in the regions having lowpressure while the vacuum pump 122 is drawing from the test system 104.It has been found that the RH in the low pressure region 222 mayincrease up to 10% while the shut-off valve 240 is closed during a soakperiod.

The by-pass valve 242 is opened while the shut-off valve 240 is closedto couple the HEPA filter 246 to the inlet of the vacuum pump 122. Thevacuum pump 122 may then draw air through the HEPA filter 246 whileisolated from the test system 104 to avoid damage to the vacuum pump122.

FIGS. 2C-D depict another embodiment of the flow reverser 124. In theembodiment depicted in FIG. 2C, the flow reverser 124 is a 4-way valvethat includes a first port 252 connected to the test system 104, asecond port 254 connected to the containment housing 102, a third port256 connected to an inlet of the vacuum pump 122 and a fourth port 258connected to an outlet of the vacuum pump 122. The flow reverser 124 maybe operated by an actuator, such as the actuator 214, to changeoperational state of the flow reverser 124.

A first operational state of the flow reverser 124 is depicted in FIG.2C. In the first operational state of the flow reverser 124, the firstport 252 is coupled to the third port 256 and the second port 254 iscoupled to the fourth port 258. In the first operational state, thevacuum pulled by the vacuum pump 122 creates pressure gradient acrossthe test system 104 as discussed above.

A second operational state of the flow reverser 124 is depicted in FIG.2D. In the second operational state of the flow reverser 124, the firstport 252 is coupled to the fourth port 258 and the second port 254 iscoupled to the third port 256. In the second operational state, thevacuum pulled by the vacuum pump 122 pulls air, which includessterilization agent previously introduced to the containment housing102, through the vacuum pump 122 and pushes the air and sterilizationagent into the test system 104, thereby reversing the pressure gradientpreviously created in the test system 104 while the flow reverser 124was in the first operational state. Since the pressure gradient in thetest system 104 produced with the flow reverser 124 in the secondoperational state is the opposite of the pressure gradient produced whenthe flow reverser 124 is in the first operational state, the pressuregradient in the test system 104 now has a low pressure region proximatethe test system 104 and a high pressure region proximate the flowreverser 124 and pump 122. Thus, reversing of the pressure gradientallow high concentrations of the sterilization agent to be presentduring at least a portion of the decontamination cycle in every regionof the tubing and other equipment comprising test system 104.

FIG. 3 is a flow diagram of one embodiment of a method 300 fordecontaminating tubing, such as tubing 106 coupling the test system 104to the contamination housing 102 and/or tubing within the test system104 itself. In one embodiment, the method 300 begins by flowing asterilization agent from the decontamination system 130 through thetubing of test system 104 in a first direction at step 302. If thesystem consists of multiple loops or circuits controlled by valves,these circuits may be charged simultaneously or sequentially byoperating the valves accordingly. During step 302, the flow reverser 124is in the first operational state. The duration of step 302 may be fromabout 1 second to about 5 minutes, depending on the volume of thecircuit. An acceptable cycle involving multiple circuits might includesequential charging of each circuit for 5 to 30 seconds and a forwardflow direction time of 10 seconds to 10 minutes depending upon the exactconfiguration of the system. In other systems, the flow direction may bereversed by reversing the direction of the vacuum pump 122.

At an optional soak step 304, the shut-off valve 240 may be closed andthe by-pass valve 242 may be opened to allow the sterilization agent inthe test system 104 to soak (i.e., be in a substantially non-flowcondition). Soaking allows the sterilization agent to disperse with thetest system 104 while allowing for pressure to rise in areas of lowpressure generated during step 302, such as the region of the testsystem 104 proximate the vacuum pump 122. The duration of the soak step304 may be from about 10 seconds to about 10 minutes, such as about 1minute to about 6 minutes. It is contemplated that the soak step 304 maybe performed without use of the shut-off valve 240 and the by-pass valve242 by turning off the vacuum pump 122, and optionally, changing thestate of the flow reverser 124.

At step 306, the flow of the sterilization agent through the tubing 106of test system 104 is reversed. The flow of the sterilization agentthrough the tubing 106 of test system 104 may be reversed by changingthe operational state of the flow reverser 124 to the second operationalstate. The duration of the soak step 304 may be from about 10 seconds toabout 10 minutes, such as about 1 minute to about 6 minutes.

At an optional soak step 308, the shut-off valve 240 may be closed andthe by-pass valve 242 may be opened to allow the sterilization agent inthe test system 104 to soak after step 306. The soak step 308 may beshorter than the soak step 304. It is contemplated that the soak step308 may be performed without use of the shut-off valve 240 and theby-pass valve 242 by turning off the vacuum pump 122, and optionally,changing the state of the flow reverser 124. The duration of step 308may be from about 10 seconds to about 10 minutes, such as about 1 minuteto about 6 minutes. At an optional step 310, the sequence of steps 302,306 may be repeated as many times as desired. One or more of theoptional soak steps 304, 308 may also be repeated at step 310. It iscontemplated that the sterilization agent may be any sterilization agentsuitable to decontaminate surfaces of hazardous particles fromcontainment systems including, but not limited to formaldehyde (CH₂O)and chlorine dioxide (ClO₂), Hydrogen Peroxide (H₂O₂) among others. Thetarget concentration of the sterilization agent and the duration of thedecontamination cycle are a function of the sterilization agent used,the hazardous particles in the system, and other factors that may bespecific to a particular application. The above example is providedutilizing Chlorine Dioxide as a sterilization agent, and a test systemhaving an enclosed volume of approximately 5 cubic feet comprised ofapproximately 300 feet of 0.25 inch inside diameter tubing, 20 feet of0.75 inch inside diameter tubing and other system components includingfilters, junction box(es), humidifier(s) and valves that contribute tototal system volume. FIG. 4 is a graph 400 illustrating the flow changeswithin the test system 104 during one embodiment of the method 300. Thegraph 400 includes a flow trace 402 with flow on the vertical axis 404and time on the horizontal axis 406. In the embodiment of the method 300depicted in the graph 400, optional soak steps 304 and 308 are included.Flow in the first direction though the test system 104 is illustrated asa positive value on the vertical axis 404 while flow in the oppositedirection (e.g., second direction) is illustrated as a negative value onthe vertical axis 404.

FIG. 5 is depicts a simplified schematic diagram of one embodiment of adecontamination system 500 that may be utilized with a containmentsystem 100 having a test system 502. The test system 502 issubstantially identical to the reversible flow test system 104 describedabove, except for that the flow reverser 124 is optional. Thedecontamination system 500 incorporates a humidifier 504 to providebetter control of the humidity in the test system 502 duringsterilization, and as such, provides increased effectiveness of thedecontamination process. The humidifier may be of various designsincluding thermal, ultrasonic or aerosol nozzle types.

Referring additionally to FIG. 6, the decontamination system 500includes a sterilization agent generator 602 coupled to the humidifier504. The sterilization agent generator 602 may be any suitablesterilization agent generator now known or developed in the future.

The humidifier 504 includes a canister 604 sealed by a lid 606. In oneembodiment, a gasket 628 is disposed between the canister 604 and thelid 606 to provide a seal therebetween. At least one of the canister 604or the lid 606 includes a fill port 608, an inlet port 610, a heaterport 612, a thermocouple port 614 and an outlet port 616. The fill port608 may be sealed by a cap or plug 618, which may be removed to allow aninterior volume 620 of the canister 604 to be filled with a fluid 650,such as water, to an appropriate level for humidity generation. Theinlet port 610 is coupled to an output port 622 of the sterilizationagent generator 602 by a tee 624. A bubbler 626 is disposed in theinterior volume 620 of the humidifier 504 and coupled to the inlet port610. The bubbler 626 allows the sterilization agent to be bubbled upthrough the fluid disposed in the humidifier 504 to generate a mixtureof sterilization agent and water vapor within the interior volume 620.

A resistive heater 630 is provided to heat the fluid and/or water vaporin the humidifier 504. The resistive heater 630 may be disposed on theexterior of the canister 604 or in the interior volume 620 of thehumidifier 504 as shown in FIG. 6. A thermocouple 632 is disposed in thehumidifier 504 to provide a metric indicative of the temperature of thefluid and/or water vapor in the humidifier 504. The resistive heater 630and thermocouple 632 are coupled through the heat and thermocouple ports612, 614 to a controller 634 to provide control of the temperature ofthe fluid and/or water vapor in the humidifier 504.

The mixture of sterilization agent and water vapor generated within theinterior volume 620 of the canister 604 exits the humidifier 504 throughthe outlet port 614. A cooling coil 636 and steam trap 638 are coupledto the outlet port 614 to minimize the amount of liquid entrained in themixture leaving the humidifier 504. The mixture of sterilization agentand water vapor is mixed in with the sterilization agent from thesterilization agent generator 602 at a tee 640, which couples thecombined flows to the test system 502.

The decontamination system 500 having the humidifier 504 coupled inparallel to the output of the sterilization agent generator 602 hasillustrated a beneficial increase in humidity levels in the test system502 during decontamination over conventional designs. Thedecontamination system 500 has been able to maintain the humidity withinthe test system 502 in the range of 60 to 80% RH, which provides moreefficient sterilization of the tubing utilized in the test system 502.As discussed above, the decontamination system 500 may be utilized inthe tube sterilization method 300 described above, or in otherdecontamination processes. It is also anticipated that in anotherembodiment, the humidifier described above can be fitted with a portallowing the introduction of reagents to generate the decontaminationagent, thereby allowing the humidifier to also act as a decontaminationagent generator as well.

FIG. 7 is a sectional schematic view of another embodiment of acontainment system 700. The containment system 700 ensures that airexiting or being recycled in a facility is substantially free ofhazardous matter. The containment system 700 is similar to the housingsdescribed above and generally includes a housing 702 having one or morefilters 706 disposed therein.

In one embodiment, the housing 702 includes a filter mounting portion704 for sealingly mounting the filter 706 to the housing, an airflowinlet aperture 708 and an airflow exit aperture 710. Each aperture 708,710 has a damper 712, 714 for controlling the flow of air through thehousing 702 and filter 706. In one embodiment, the dampers 712, 714 maybe configured with a bubble-tight seal so that leakage may be preventedthrough the apertures 708, 710.

The housing 702 includes a sealable filter access port 720 formedthrough the housing 702 adjacent the filter mounting portion 704 tofacilitate installation and replacement of the filter 706. As commonpractice, the sealable filter access port 720 includes a bag-in bag-outsystem 721 to prevent exposure of technicians to hazards during filterreplacement.

The housing 702 also includes a test section 716 and a plenum section738. The test section 716 is positioned downstream of the filtermounting portion 704 while the plenum section 738 is positioned upstreamof the filter mounting portion 704. The test section 716 includes one ormore downstream sample ports utilized to test the filter 706 disposed inthe housing 702. The plenum section 738 is generally configured toprovide sufficient space for mixing elements to provide an evendistribution of aerosol challenge upstream of the filter 706.

A plurality of sample ports 718 are formed through the housing 702 toaccommodate taking samples from the test section 716 and deliveringaerosol to the plenum section 738. Each port 718 is fitted with a valveassembly 750. The valve assembly 750 is selectable between at leastthree states. In a first state, the valve assembly 750 prevents flowthrough the port 718. In a second state, the valve assembly 750 fluidlycouples the port 718 to a test system 790 that includes the testequipment necessary to test the filter 706 disposed within the housing702, such as an aerosol generator, dilutor and sampling system 722. In athird state, the valve assembly 750 seals the port 718 but fluidlycouples the test system 790 to a decontamination system 724.

The decontamination system 724 generally provides an agent suitable forneutralizing hazardous agents that may be present in the test system 790after testing the filter 706. The decontamination system 724 mayadditionally be utilized to decontaminate the housing 702 prior tofilter testing or as desired. The decontamination system 724 mayoptionally be configured similar to the decontamination system 500described above to include a humidifier 504 that raises the humidity ofthe sterilization agent being provided to the contamination housing 702and test system 790 in the ranges discussed above. The valve assembly750 will be described in greater detail below.

In the embodiment depicted in FIG. 7, the downstream sample ports 718disposed in the test section 716 comprises one or more probes 732 and asupport structure 734. The support structure 734 couples the one or moreprobes 732 to the housing 702. The support structure 734 may staticallyhold the probes in a predefined position, or may be configured with oneor more actuators, such as an x/y displacement mechanism, whichdynamically positions (e.g., scans) the probe 732 along the downstreamsurface of the filter 706. The one or more probes 732 may have a designsuitable for scan and/or efficiency testing. In one embodiment, the oneor more probes 732 conform to IEST-RP-CC034 Recommended Practices.

The valve assembly 750 can be a single valve or a plurality of valves.The valve assembly 750 can have mechanical or automated actuation. Thevalve assembly 750 can include a manual or electronic lockout. Thelockout prevents inadvertent actuation of the valve assembly 750.Further, the valve assembly 750 can have position sensors 752 (shownschematically) that provide the controller with a metric indicative ofthe state of the valve. The controller, in response to a metric, canelectronically lockout the valve assembly 750 to prevent change in stateof the valve assembly 750 so that the routing of gas flow through thevalve assembly 750 cannot be changed. Further, the valve assembly 750can have a sensor 754 (shown schematically) to determine if lines to thesample system 722 and/or decontamination system 724 are coupled to valveassembly 750 to prevent inadvertent actuation.

A valve assembly 750 is respectively coupled to a corresponding sampleport 718, as shown in FIG. 8A-2C. The one or more valve assemblies 750allow an operator to selectively control the flow between the testsection 716, plenum section 738, the sample system 722 of the testsystem 790, and the decontamination system 724. In one embodiment, eachof the one or more valve assemblies 750 includes an isolation valve 802and a decontamination valve 804. The valve assembly 750 alternativelymay also be a single selector valve configured to seal the sample port718, allow flow between the test section 716 and the sample system 722,the test section 716 and the decontamination system 724, or thedecontamination system 724 and the sample system 722. The valveassemblies 750 can each comprise a first port 850, a second port 852 anda third port 854. The first port 850 fluidly couples the valve assembly750 to the sample port 718. The second port 852 fluidly couples valveassembly 750 to the decontamination system 724. The third port 854fluidly couples the valve assembly 750 to the sample system 722.

FIG. 8A depicts one embodiment of the valve assembly 750. The valveassembly 750 comprises an isolation valve 802 and a decontaminationvalve 804 configured to control flow between the test section, thesample system 722 and the decontamination system 724. The upstream ofthe isolation valve 802 is coupled to the port of the housing 702. Thedownstream side of the isolation valve 802 is coupled to a tee fitting806 at a first tee port 856. The second side of the tee fitting 806 iscoupled to the decontamination system 724 through the decontaminationvalve 804 at a second tee port 858. The third side of the tee fitting806 is coupled to the sample system 722, at a third tee port 860.

The isolation valve 802 is in fluid communication with the correspondingsample port 718. The isolation valve 802 selectively isolates the samplesystem 722 from the test section 716 or the plenum section 738. As shownin FIGS. 8A-2C, the isolation valve 802 is in the closed position. Inthe closed position, the isolation valve 802 prevents fluid flow fromexiting the test section 716 through the sample port 718.

The decontamination valve 804 is in fluid communication with the samplesystem 722. The decontamination valve 804 selectively isolates thedecontamination system 724 from the tee fitting 806. As shown in FIGS.8A-2C, the decontamination valves 804 are in the closed position. In theclosed position, the decontamination valve 804 prevents fluid flow fromthe decontamination system 724 to the sample system 722.

In one embodiment, the isolation valve 802 and the decontamination valve804, as shown in FIG. 8A-2C, are both hand operated ball valves.However, it is contemplated that any valve capable of selectivelycontrolling and isolating flow may be used including, but not limitedto, a single selector valve, a gate valve, a spool valve, a pneumaticvalve, a solenoid valve, a control valve or other suitable flow controldevice. Although the valve assembly 750 is shown as being hand operated,it is contemplated that the valve assembly 750 may be automaticallyactuated to change the state of the valve. Thus, the operation of one orboth of the isolation valve 802 and the decontamination valve 804 may beautomatically controlled from a controller 836. For example, the valveand/or valves comprising one or more of the valve assemblies 750 mayinclude an automatic actuator 870 (shown in phantom). The automaticactuator 870 may be a servo motor, a stepper motor, a rotary actuator, apneumatic or hydraulic actuator, a linear actuator, solenoid or otheractuator suitable for changing the state of the valve in response to asignal from the controller 836.

The valve assembly 750 may also include the sensor 752 and/or 754 thatprovides the controller 836 with a signal indicative of the position(i.e., flow state) and/or if the valve is connected to a conduit (sothat fluids can not inadvertently exit the valve into surroundingenvironment), thus enabling a lockout if the valves are not properlysequenced or are in an unintended state. The lockout may be mechanical,or electronic. The sensors 752, 754 may be a flow sensor interfaced withthe fluid conduits of the valve assembly, a proximate indicatorconfigured to detect if the valve assembly 750 is coupled to appropriateconduits, or an encoder, limit switch or other sensor suitable fordetecting the open and/or closed state of the one or more valvescomprising the valve assembly 750.

In an alternative embodiment, one or both of the isolation valve 802 andthe decontamination valve 804 may include a one-way (check) valve. Theone-way valve associated with the isolation valve 802 may be arranged toallow fluid flow from the test section 716 to the sample system 722while preventing flow in the opposite direction. The one-way valveassociated with the decontamination valve 804 may be arranged to allowfluid flow from the decontamination system 724 to the sample system 722while preventing flow in the opposite direction.

FIG. 8B depicts the containment system 700 coupled to the test system790, an aerosol generator 822 and the decontamination 724 system tofacilitate in-situ testing of the filter 706 disposed in the housing702. The decontamination system 724 selectively decontaminates the testsystem 790, the aerosol generator 822, and/or the dilutor 824. Thedecontamination valves 804 may be selectively opened to allow adecontamination agent to enter the sample system 722 of the test system790. The isolation valve 802 is generally closed while thedecontamination valve 804 is open. The isolation valves 802 selectivelyprevent the agents from the decontamination system 724 from entering theinterior of the housing 702 through the sample ports 718. Thedecontamination system 724 circulates a sterilization (decontamination)agent through any of the systems to be decontaminated. As shown, thedecontamination system 724 couples to the decontamination valves 804 viaone or more decontamination lines 835. The decontamination lines 835couple directly to the decontamination valves 804 or to an intermediatecoupler, such as a decontamination manifold 813, between thedecontamination valves 804 and the decontamination lines 835. Theintermediate coupler may be any device for sealingly coupling thedecontamination system 724 to the decontamination valve 804. Forexample, the intermediate coupler may be a quick connect. Theintermediate coupler allows an operator to quickly couple thedecontamination lines 835 to the decontamination valves 804.

The aerosol generator 822 supplies an aerosol challenge to the upstreamside of the filter 706 through at least one of the valve assemblies 750coupled to the plenum section 738. The aerosol generator 822 provides anaerosol to the plenum section 738 of sufficient concentration to providea statistically valid test of the filter 706. The aerosol generator 822may be coupled to the sample manifold 820 through a decontaminationreturn valve 807.

The test system 790 measures the particles present in the air samplestaken from the test section 716 and plenum section 738 of thecontainment system 700 through the sample ports 718 of that leak orefficiency determinations may be make. The test system 790 includes asample system 722, a dilutor 824, one or more lines 814, and an exhaustfilter 744. The one or more lines 814 (Le., tubing) convey the airsamples to the filter test equipment of the sample system 722. Thefilter test equipment may be a photometer, particle counter, or otherequipment suitable for leak and/or efficiency testing of the filter 706.The filter test equipment provides a metric indicative of the number ofparticles present in the air samples. The measured air sample exitingthe filter test equipment is exhausted from the sample system 722through the exhaust filter 744. In embodiments wherein the vacuum pump742 is directly coupled to the decontamination system 724, the filter744 may be omitted.

The dilutor 824 is also coupled to the upstream side of the filter 706through at least one of the valve assemblies 750 coupled to the plenumsection 738. The dilutor 824 is provided a sample of the air and aerosolpresent in the plenum section 738 through the valve assembly 750 whenthe isolation valve 802 is open and the decontamination valve 804 isclosed. The dilutor 824 is configured to dilute the upstream sample apredefined amount so that the concentration of particles provided to thefilter test equipment of the sample system 722 is within the operationallimits of the filter test equipment so that an upstream concentrationlimit may be calculated for use in determining the filtration efficiencyand/or leak threshold.

The one or more lines 814 coupling the one or more valve assemblies 750to the filter test equipment of the sample system 722 may each becoupled to a solenoid valve 818 so that samples from each line may besequenced through the filter test equipment. The solenoid valves 818 maybe independently operated and controlled. In one embodiment, eachsolenoid valve 818 controls the flow from each line 814 into a samplemanifold 820. The common outlet of the sample manifold 820 is fluidlycoupled to the filter test equipment of the sample system 722. In thisembodiment, any one, or combination, of the solenoid valves 818 may openin order to test the air sample from that particular probe 732 (ordilutor 824) associated with the corresponding valve assembly 750.

A decay bypass valve 805 may be coupled to the upstream side of thefilter 706 through at least one of the valve assemblies 750 coupled tothe plenum section 738. In one embodiment, the decay bypass valve 805couples the inlet of the dilutor 824 to the outlet of the filter testequipment of the sample system 722. In this embodiment, the decay bypassvalve 805 may open in order to allow more rapid evacuation of thehousing and system when performing vacuum pressure decay tests.

In one embodiment, the air leaving the filter test equipment of thesample system 722 passes through an exhaust filter 744. The exhaustfilter 744 prevents hazardous particles which may be within the samplesystem 722 from being passed to the environment after sampling. Theexhaust filter 744 may be any suitable filter.

The sample system 722 may optionally include a vacuum pump 742. Thevacuum pump 742 aides in circulation of the air sample and/or asterilization agent from the decontamination system 724 through thesample system 722. Any suitable pump or compressor may be used so longas the pump or compressor is compatible the sterilization agent.

Optionally, a flow reverser 740 (shown in phantom) may be disposedbetween the sample system 722 and the vacuum pump 742. The flow reverser740 is similar to the flow reversers described above, and operates toreverse the flow direction of sterilization agent within the test system722, for example, to enable performance of the method 300 describedabove with reference to FIG. 3. In another embodiment, the vacuum pump742 may be a reversible pump that enables reversing the flow directionof sterilization agent within the test system 722 without the need of aflow reverser 740.

A bypass filter 832 may be coupled to the sample manifold 820. Thebypass filter 832 may be any suitable filter, for example a HEPA filter.Air flow from the bypass filter 832 to the sample manifold 820 can beselectively controlled by a bypass valve 834. As shown, the bypass valve834 is a solenoid valve, but may be any suitable valve. The bypassfilter 832 provides air to the filter test equipment of the samplesystem 722 when the solenoid valves 818 interfaced with the one or morelines 814 are closed. The bypass filter 832 allows the pump of thefilter test equipment of the sample system 722 to continue to circulateair. This prevents the pump or compressor from failing, therebyextending the service life of the filter test equipment of the samplesystem 722.

Referring primarily to FIG. 8B, the controller 836 includes controllines 838 for communicating with the various components of the samplesystem 722, the decontamination system 724, the valve assemblies 800,the solenoid valves 818, 830 and/or 834, the dilutor 824, and/or theaerosol generator 822. The controller 836 sends and receives data viathe control lines 838. Optionally, the controller 836 may communicateusing fluid, pneumatic, and/or wireless (e.g., infrared, RF, Bluetooth,etc.) signals with components described herein. The controller 836 maybe configured to operate and monitor each of the respective componentsin an automated fashion (e.g., according to a preprogrammed sequencestored in memory) or according to explicit user input.

Although not shown, the controller 836 may be equipped with aprogrammable central processing unit, a memory, a mass storage device,and well-known support circuits such as power supplies, clocks, cache,input/output circuits, and the like. Once enabled, an operator maycontrol the operation of the containment system 700, the sample system722, the decontamination system 724, the aerosol generator 822 and thedilutor 824 by inputting commands into the controller 836. To this end,another embodiment of the controller 836 includes a control panel, notshown. The control panel may include a key pad, switches, knobs, a touchpad, etc. The controller 836 may further comprise a visual display.

During normal operation of the containment system 700 the valveassemblies 750 are in the first state. In the first state, the valveassemblies 750 prevent flow through the ports 718. In one embodiment,the isolation valve 802 is closed in the first state. The first stateallows the containment system 700 to filter facility air through thehousing 702 without contaminating the sample system 722. The valveassembly 750 remains in the first state until a filter test and/orcertification is desired. When the filter test is desired, the samplesystem 722 is coupled to the valve assemblies 750.

To test the filter 706, the valve assemblies 750 are placed in thesecond state. In the second state, the valve assemblies 750 fluidlycouple the ports 718 to the filter test equipment of the sample system722 of the sample system 722 that are necessary to test the filter 706disposed within the housing 702. In one embodiment, the second state isachieved by opening the isolation valve 802 while the decontaminationvalve 804 remains closed.

An aerosol challenge is provided by the aerosol generator to the plenumsection of the housing 702 through the appropriate valve assembly 750.After the upstream challenge concentration has stabilized within thehousing, the appropriate solenoid valve 818 is opened to allow thedilutor 824 to provide a sample to the filter test equipment of thesample system 722 so that the upstream concentration and/or leakthreshold may be established. The appropriate solenoid valves 818 areactuated to provide downstream samples obtained through the probes 732to the filter test equipment of the sample system 722. From thedownstream samples, the filter efficiency and/or location of a leak maybe determined. The pump or compressor of the filter test equipment ofthe sample system 722 can pull the air sample from the test section 716.The air sample travels via the one or more tubes 736 through the wall ofthe housing 702 and through the one or more valve assemblies 750. Theair sample travels past the valve assemblies 750 and into the one ormore lines 814 of the sample system 722. The decontamination system 724remains isolated from the sample system 722. This prevents the flow ofthe air sample into the decontamination system 724 while causing the airsample to enter the sample system 722.

The air sample travels to the filter test equipment of the sample system722 for testing. The filter test equipment of the sample system 722tests the air sample. The filter test equipment of the sample system 722can directly store and/or convey the information from the test to anoperator or the controller 836 via the control lines 838. The air sampleexhausts from the filter test equipment of the sample system through theexhaust filter 744. The exhaust filter 744 may recirculate the filteredair sample back into the facility, the housing 702, or thedecontamination system 724. This process continues until the test iscomplete.

Advantageously, the in-situ testing of the filter is completed withoutdecontaminating the housing 702. By not decontaminating the housingprior to testing, significant time is saves which can be utilized foroperational activities of the facilities. Moreover, since the largevolume of the housing, laboratory or bio-safety cabinet or other devicesin the facility are not exposed to decontamination agents, the amount ofdecontamination agents utilized is significantly reduced.

Upon completion of the filter test, the valve assemblies 750 areactuated to the third state. In the third state, flow is preventedthrough the valve assembly 750 into the housing 702, while flow isprovided between the decontamination system and the sample system.Selectively, the dilutor 824, aerosol generator 822, sample manifold 820and filter test equipment of the sample system 722, and exhaust filter744 may be exposed to the decontamination agents. The decontaminationcycle may be enhanced by the optional use of at least one of ahumidifier 504, flow reverser 740 or other process for compensating forlow pressure regions in the test system 790 during portions of thedecontamination cycle.

An operator or the controller 836 may be utilized to actuate the valveassemblies 750. In one embodiment, the third state includes having thedecontamination valve 804 in an open state while the isolation valve 802is a closed state. To decontaminate the sample system 722, thesterilization agent flows from through the decontamination valve 804 andinto the one or more valve assemblies 750 into the sample system 722.The solenoid valves 818 are held in an open state or cycled open andclosed. The dilutor 824, and optionally, the aerosol generator 822 aredecontaminated in as described above. The isolation valve 802 remainsclosed thereby preventing the flow of the sterilization agent into thehousing 702. The sample system 722 may circulate the sterilization agentin the same manner as the air samples. Thus, the sterilization agentflows through all of the potentially contaminated components of thesample system 722, the aerosol generator 822, and the dilutor 824 whilethe containment system remains in an operational state, therebycontributing to the cost effective operation of the facility. The flowof the sterilization agent may be reversed within the tubing of thesample system 722 one or more times. Additionally, or in thealternative, the control of the humidity of the sterilization agent inthe sample system 722 may be eliminated through the use of thehumidifier 504. The sterilization agent may be recirculated back intothe decontamination system 724. The duration of the decontaminationprocess is a function of the hazardous particles to be decontaminated.With the decontamination complete the valve assemblies 750 may return tothe first state. The decontamination lines 835 can uncouple from the oneor more valve assemblies 750. The decontamination system 724 and/or thesample system 722 may then be moved to another housing 702 of the sameor a separate containment system 700. The process may be repeated tocertify another filter.

The embodiments described herein enable HEPA and carbon filters incontainment, glove box, biological safety cabinets, transfer units,isolators and other filtration systems to be certified for leaks viascan testing and/or overall efficiency testing without having todecontaminate or sterilize the housing in which the filter is installedprior to conducting filter certification. This eliminates the need todecontaminate or sterilize laboratories, work spaces, clean spaces,production areas, glove boxes, clean benches or other areas or systemsserviced by the containment and filtration systems described above. Thisis advantageous in that it reduces facility down-time associated withhaving to decontaminate systems or areas listed above. Reducing thefacility down time can equate to higher yields, production capacity,profitability or experiment duration. Further, the system provides acost-effective method to certify filters after an “upset” conditionwithout having to shut down the experiment and potentially lose monthsor even years worth of time, money and investment, as well aseliminating potential adverse impacts on socially critical experimentsor processes.

While the foregoing is directed to embodiments of the present invention,other and further embodiments of the invention may be devised withoutdeparting from the basic scope thereof, and the scope thereof isdetermined by the claims that follow.

1. A test system for a containment system, the containment system havinga containment housing having an airflow inlet aperture, an airflowoutlet aperture, a bag-in/bag-out filter access port, a filter mountingportion disposed between the inlet and outlet apertures and configuredto sealingly secure a filter in the containment housing in a positionthat filters air flowing between the inlet and outlet apertures throughthe containment housing, a plurality ports formed through thecontainment housing, wherein the ports include at least a downstreamsample port and an upstream sample port, the test system comprising: asample system including equipment adapted for testing the filterdisposed in the containment system utilizing samples obtained from thedownstream sample port and an upstream sample port; and a device forreversing a flow within the sample system.
 2. The test system of claim1, wherein the device for reversing a flow within the sample systemcomprises: a reversible vacuum pump.
 3. The test system of claim 1,wherein test system further comprises: a vacuum pump having in inletcoupled to the sample system, and wherein the device for reversing aflow within the sample system comprises: at least one valve having afirst state that allows flow from the sample system into the vacuumpump, the flow causing a first directional flow within the samplesystem, and a second state that prevents flow from the sample systeminto the vacuum pump, the at least one valve also allowing a seconddirectional flow through the sample system that is opposite of the firstdirectional flow.
 4. The test system of claim 1, wherein test systemfurther comprises: a vacuum pump having in inlet coupled to the samplesystem, and wherein the device for reversing a flow within the samplesystem comprises: at least one valve having a first state that couplesthe inlet of the vacuum pump to the sample system and a second statethat couples an outlet of the vacuum pump to the sample system.
 5. Amethod for decontaminating tubing, comprising: flowing a sterilizationagent through tubing in a first direction; and flowing the sterilizationagent through tubing in a second direction.
 6. The method fordecontaminating tubing of claim 5, wherein flowing the sterilizationagent through tubing further comprises: flowing the sterilization agentthrough filter test equipment, wherein the filter test equipmentcomprises at least one of a diluter, a photometer and a particlecounter.
 7. The method for decontaminating tubing of claim 5 furthercomprising: soaking the sterilization agent in the tubing between thesteps of flowing the sterilization agent through tubing in the firstdirection and flowing the sterilization agent through tubing in thesecond direction.
 8. The method for decontaminating tubing of claim 5,further comprising: operating a vacuum pump to flow the sterilizationagent through the tubing in the first direction.
 9. The method fordecontaminating tubing of claim 8, further comprising: reversing adirection of the vacuum pump to change the flow through the tubing fromthe first direction to the second direction.
 10. The method fordecontaminating tubing of claim 8, further comprising: actuating one ormore valves to change the flow through the tubing from the firstdirection to the second direction, wherein the one or more valves have afirst state that couples an inlet of the vacuum pump to tubing disposedin a sampling system and a second state that couples an outlet of thevacuum pump to tubing disposed in the sampling system.
 11. The methodfor decontaminating tubing of claim 8, further comprising: isolating thevacuum pump from the sampling system while flowing the sterilizationagent in the second direction.
 12. The method for decontaminating tubingof claim 5, further comprising: maintaining a relative humidity levelwithin the sampling system between about 60 to 80% RH.
 13. The methodfor decontaminating tubing of claim 12, further comprising: generatingthe sterilization agent in a sterilization agent generator; separating aflow of the sterilization agent into a first stream and a second stream;flowing the first stream of the sterilization agent through ahumidifier; combining the first stream of the sterilization agentexiting the humidifier with the second stream of the sterilization agentto define a humidified stream of the sterilization agent; and flowingthe humidified stream of the sterilization agent into the samplingsystem in the first direction.
 14. The method for decontaminating tubingof claim 5, wherein the sterilization agent is formaldehyde or chlorinedioxide or hydrogen peroxide or mixtures of these or mixtures of one ofthese agents with other chemicals, gasses or vapors or their mixtures.15. A method for decontaminating tubing in a test system coupled to acontainment system, the containment system having a containment housinghaving an airflow inlet aperture, an airflow outlet aperture, abag-in/bag-out filter access port, a filter mounting portion disposedbetween the inlet and outlet apertures and configured to sealinglysecure a filter in the containment housing in a position that filtersair flowing between the inlet and outlet apertures through thecontainment housing, a plurality ports formed through the containmenthousing, wherein the ports include at least a downstream sample port andan upstream sample port coupled to the test system, the test systemhaving at least one of a diluter, a photometer and a particle counter,components of the test system coupled by the tubing, the methodcomprising: operating a vacuum pump to create a flow of sterilizationagent in the test system in a first flow direction; and reversing theflow direction of the sterilization agent in the test system.
 16. Themethod for decontaminating tubing of claim 15 further comprising:soaking the sterilization agent in the tubing prior to reversing theflow direction of the sterilization agent.
 17. The method fordecontaminating tubing of claim 15, wherein reversing the flow directionof the sterilization agent in the test system further comprising: atleast one of operating the vacuum pump in a reverse direction orisolating an inlet of the vacuum pump from the test system.
 18. Themethod for decontaminating tubing of claim 15, wherein reversing theflow direction of the sterilization agent in the test system furthercomprising: actuating one or more valves to reverse the flow of thesterilization agent through the tubing, wherein the one or more valveshave a first state that couples an inlet of the vacuum pump to tubingdisposed in a test system and a second state that couples an outlet ofthe vacuum pump to tubing disposed in the test system.
 19. The methodfor decontaminating tubing of claim 15, further comprising: maintaininga relative humidity level within the sampling system between about 60 to80% RH.
 20. The method for decontaminating tubing of claim 15, furthercomprising: separating a flow of the sterilization agent into a firststream and a second stream prior to introduction into the test system;flowing the first stream of the sterilization agent through ahumidifier; combining the first stream of the sterilization agentexiting the humidifier with the second stream of the sterilization agentto define a humidified stream of the sterilization agent; and flowingthe humidified stream of the sterilization agent into the samplingsystem in the first direction.